EP1140331B1 - Procede de fabrication d'une membrane polyolefinique integralement asymetrique - Google Patents

Procede de fabrication d'une membrane polyolefinique integralement asymetrique Download PDF

Info

Publication number
EP1140331B1
EP1140331B1 EP00909086A EP00909086A EP1140331B1 EP 1140331 B1 EP1140331 B1 EP 1140331B1 EP 00909086 A EP00909086 A EP 00909086A EP 00909086 A EP00909086 A EP 00909086A EP 1140331 B1 EP1140331 B1 EP 1140331B1
Authority
EP
European Patent Office
Prior art keywords
compound
process according
temperature
polymer component
membrane
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP00909086A
Other languages
German (de)
English (en)
Other versions
EP1140331A1 (fr
Inventor
Erich Kessler
Thomas Batzilla
Friedbert Wechs
Frank Wiese
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Membrana GmbH
Original Assignee
Membrana GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Membrana GmbH filed Critical Membrana GmbH
Publication of EP1140331A1 publication Critical patent/EP1140331A1/fr
Application granted granted Critical
Publication of EP1140331B1 publication Critical patent/EP1140331B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002Organic membrane manufacture
    • B01D67/0009Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
    • B01D67/0018Thermally induced processes [TIPS]
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002Organic membrane manufacture
    • B01D67/0023Organic membrane manufacture by inducing porosity into non porous precursor membranes
    • B01D67/0025Organic membrane manufacture by inducing porosity into non porous precursor membranes by mechanical treatment, e.g. pore-stretching
    • B01D67/0027Organic membrane manufacture by inducing porosity into non porous precursor membranes by mechanical treatment, e.g. pore-stretching by stretching
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002Organic membrane manufacture
    • B01D67/0023Organic membrane manufacture by inducing porosity into non porous precursor membranes
    • B01D67/003Organic membrane manufacture by inducing porosity into non porous precursor membranes by selective elimination of components, e.g. by leaching
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D69/00Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/02Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D69/00Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/08Hollow fibre membranes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/26Polyalkenes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/26Polyalkenes
    • B01D71/261Polyethylene
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/26Polyalkenes
    • B01D71/262Polypropylene
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/28Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2323/00Details relating to membrane preparation
    • B01D2323/08Specific temperatures applied
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2323/00Details relating to membrane preparation
    • B01D2323/08Specific temperatures applied
    • B01D2323/082Cooling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2323/00Details relating to membrane preparation
    • B01D2323/12Specific ratios of components used
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/02Details relating to pores or porosity of the membranes
    • B01D2325/022Asymmetric membranes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2325/00Details relating to properties of membranes
    • B01D2325/02Details relating to pores or porosity of the membranes
    • B01D2325/026Sponge structure

Definitions

  • the invention relates to a method for producing a hydrophobic membrane a thermally induced phase separation process according to the preamble of the claim 1, the membrane being a sponge-like, open-pore microporous Contains structure, as well as the use of the membrane for gas exchange processes, especially for oxygenation of blood.
  • oxygenators also called artificial lungs.
  • oxygenators e.g. used in open heart surgery oxygenation of blood and removal of carbon dioxide from the blood.
  • bundles of hollow fiber membranes become in such oxygenators used.
  • Venous blood flows outside around the hollow fiber membranes, while through the lumen of the hollow fiber membranes air enriched with oxygen Air or pure oxygen, i.e. a gas is led.
  • Air or pure oxygen i.e. a gas is led.
  • Over the membranes there is contact between blood and gas, which causes a transport of oxygen into the blood and at the same time a transport of carbon dioxide from the blood into the Gas can be done.
  • the membranes In order to supply the blood with sufficient oxygen and carbon dioxide at the same time the membranes must be able to remove them from the blood to a sufficient extent ensure high gas transport: there must be a sufficient amount of oxygen sufficient from the gas side of the membrane to the blood side and vice versa Amount of carbon dioxide is transferred from the blood side of the membrane to the gas side, i.e. the gas flows or the gas transfer rates, expressed as the volume of a Gases per unit time and membrane area from one membrane side to the other transported must be large.
  • a decisive influence on the The porosity of the membrane has transfer rates, since only with a sufficiently high porosity sufficient transfer rates can be achieved.
  • a number of oxygenators are used, the hollow fiber membranes with an open-pore microporous structure.
  • One way of using such membranes for gas exchange i.e. e.g. for oxygenation is used in the DE-A-28 33 493.
  • Membranes made of molten thermoplastic polymers with up to 90 vol .-% create interconnected pores. The process is based on a thermally induced phase separation process with liquid-liquid phase separation.
  • a homogeneous single-phase melt mixture is created first from the thermoplastic polymer and a compatible component, which forms a binary system with the polymer, which is in the liquid state an area of complete miscibility and an area with a miscibility gap has, produced and then extruded this melt mixture in a bath, the is essentially chemically inert to the polymer, i.e. essentially does not chemically react with it, and a temperature below the segregation temperature has. This initiates a liquid-liquid phase separation and upon further cooling the thermoplastic polymer to the membrane structure solidified.
  • the membranes disclosed according to DE-A-28 33 493 or DE-A-32 05 289 have an open-pore microporous structure and also open-pore microporous surfaces.
  • gaseous substances for example oxygen (O 2 ) or carbon dioxide (CO 2 )
  • O 2 oxygen
  • CO 2 carbon dioxide
  • Such membranes with gas flows for CO 2 of greater than 1 ml / (cm 2 * min * bar) and gas flows for O 2 have approximately the same size gas flows which are sufficiently large for oxygenation of blood.
  • membranes with higher plasma breakthrough time to provide greater security for longer periods To get heart surgery and to rule out a plasma breakthrough that one immediate replacement of the oxygenator would be required.
  • the goal is also, for example premature births or patients with limited temporary in general To be able to oxygenate the lung function until the lung function is restored, i.e. to be able to carry out long-term oxygenations. Therefor accordingly long plasma breakthrough times are required.
  • One in this context frequently required minimum value for the plasma breakthrough time is included 20 hours.
  • hollow fiber membranes for oxygenation which Have plasma breakthrough times of more than 20 hours, i.e. even with long-term Use no plasma breakthrough. This is otherwise the case Porous membrane with a cellular structure achieved by a barrier layer, the one average thickness of not calculated from the oxygen flow and the nitrogen flow is greater than 2 ⁇ m and is substantially impervious to ethanol.
  • the membrane is essentially free of open pores, i.e. of pores that go to both the outside as well as open to the inside of the hollow fiber membrane.
  • the membranes according to EP-A-299 381 have a corresponding to the disclosed examples Porosity of up to 31 vol .-%, since the pores with each other at higher porosities are connected and communication between the sides of the hollow fiber membranes occurs, which results in a plasma breakthrough.
  • the gases to be exchanged are transported via solution diffusion.
  • slit-shaped membranes are formed in the melt-stretching process Pores with pronounced anisotropy, a main extension of which is vertical to the direction of stretching and its second main extent perpendicular to the membrane surface lies, i.e. in the case of hollow fiber membranes between the outer surface of the membrane and Inner membrane surface runs. This extends through the pores Channels relatively straight between the surfaces.
  • leaks in the barrier layer then there is a preferred direction for the flow of a liquid between inner and outer surface or vice versa, so that a Plasma breakthrough is promoted.
  • Integrally asymmetrical are preferably made by means of the method according to the invention Membranes made with a dense separation layer.
  • a dense Structure is understood here to mean such a structure for which in the case of scanning electron microscopy Examination with a magnification of 60000 times no pores to be recognized are.
  • the method according to the invention thus allows the production of integrally asymmetrical Membranes with a long-lasting fluid breakthrough Dense, but gas-permeable separating layer and a support layer high volume porosity, which means for these membranes in gas transfer processes at the same time high gas transfer performance results.
  • These membranes can be excellent for long-term oxygenation of blood, using the interface of these membranes is responsible for making these membranes last for a long time Periods of blood plasma breakthrough are dense.
  • an integrally asymmetrical membrane is used understood a membrane in which the separating layer and the supporting layer are the same Material exist and together directly in the manufacture of the membrane were formed, connecting the two layers as an integral unit are.
  • the transition from the separating layer to the supporting layer there is only one Change in membrane structure.
  • Composite membranes that have a multilayer structure by on a porous, often microporous support layer or membrane a dense layer is applied as a separating layer in a separate process step is.
  • the materials that make up the backing and the separation layer build up, with composite membranes also different properties exhibit.
  • the method according to the invention is based on a thermally induced phase separation process with liquid-liquid phase separation.
  • a binary system that is in the liquid Physical state has an area in which the system is considered homogeneous Solution is present, and an area in which it has a miscibility gap.
  • the cooling rate has an essential one Influence on the resulting pore structure.
  • the cooling rate is sufficient great that the liquid-liquid phase separation is not under thermodynamic Equilibrium conditions can take place but under thermodynamic non-equilibrium conditions, however, on the other hand, it is still relatively slow the liquid-liquid phase separation approximately simultaneously with the formation of a large number of liquid droplets of substantially the same size.
  • the resulting The polymer structure then has a sponge-like cellular and open-pore microstructure on. If the cooling rate is significantly higher, the polymer becomes solid before most liquid droplets can form. Here arise then network-like microstructures.
  • compositions used from the polymer component, the compound A and compound B, compounds A and B together being the solvent system train together in a single homogeneous liquid phase be transferable and have a critical separation temperature below whose phase separation occurs in two liquid phases.
  • the weak components used as compound A have the polymer component / compound systems A in the liquid state a mixture gap a critical demixing temperature.
  • Compound B raises this critical separation temperature, whereby solutions with equal proportions of polymer are considered.
  • By expand compound B is a targeted control of the pore size and pore volume of the porous structures obtained.
  • Compounds A used are those compounds which are solvents for the polymer component are and in which the polymer component when heated to at most to the boiling point of this compound completely into a homogeneous solution is solved.
  • a solvent is to be used as compound A, for which the segregation temperature of a solution of 25 wt .-% of the polymer component in this solvent by less than 10% below the melting point of the pure Polymer component lies.
  • Solver called weak solver.
  • the present invention under a strong solver such a solver understood which the separation temperature of a solution of 25 wt .-% of the polymer component in this solvent by at least 14% below the melting point of the pure polymer component lies.
  • the separation or phase separation temperature can be done in a simple manner can be determined by first a homogeneous solution of the polymer component prepared in the solvent to be examined and this then to a temperature is heated, which is about 20 ° C above the dissolving temperature. This solution will approx Maintained at this temperature for 0.5 hours with stirring to ensure adequate homogeneity to ensure. The solution is then cooled at a rate of 1 ° C / min cooled with stirring. The temperature is the phase separation temperature determined, at which a beginning turbidity can be detected visually. With another Cooling occurs at the solidification temperature when the polymer-rich solidifies Phase one.
  • such a compound is selected as compound B, the one Is not a solvent for the polymer component.
  • Taking non-solvent for the polymer component is understood to mean a compound B which contains the polymer component in a concentration of 1% by weight in the non-solvent when heated to at most does not dissolve into a homogeneous solution at the boiling point of the non-solvent.
  • the compound A can additionally with one or more liquids, in particular be blended with other solvers.
  • Compound B can also be mixed with one or more further compounds, in particular further non-solvents be used.
  • the connection A not only understood a single connection, but also one Mixing different solvents, e.g. two weak solvers or one weak Solvers with portions of a stronger solver, as long as the overall effect as weak solver remains.
  • compound B there is also a mixture understood various non-solvers.
  • compound B is a weak one Non-solvent for the polymer component.
  • compound B is a weak one Non-solvent for the polymer component.
  • concentration of the polymer component is in both cases at 25% by weight.
  • a strong non-solvent is then one that increases the separation temperature by at least 10% leads.
  • the proportion of polymer required for membrane production and the ratio from connection A to connection B in the solvent system can be created of phase diagrams using simple experiments. Such phase diagrams can be developed according to known methods, e.g. by C.A. Smolders, J.J. van Aartsen, A. Steenbergen, Colloid-Z. and Z. Polymer, 243 (1971), Pp. 14-20.
  • solver A is at Using a weak non-solvent as Compound B the proportion of compound B in the mixture of the polymer component, the compound A and the Compound B should be chosen higher than when using a strong non-solvent as Compound B.
  • the proportion of compound B in the solvent system is preferably 1 up to 45% by weight.
  • At least one polymer selected from the group of polyolefins is used as the polymer component.
  • the polymer component can be a single polyolefin or a mixture of several polyolefins, the polyolefins also being polyolefin copolymers or modified polyolefins.
  • Mixtures of different polyolefins are interesting in that they can optimize various properties, such as permeability or mechanical properties.
  • the addition of small amounts of a polyolefin with an ultra-high molecular weight that is to say, for example, with a molecular weight of more than 10 6 daltons, can have a strong influence on the mechanical properties.
  • the prerequisite is of course that the polyolefins used are soluble together in the solvent system used.
  • this is in the polymer component contained at least one polymer at least one exclusively polyolefin made of carbon and hydrogen.
  • Particularly preferred Polyolefins are polyethylene, polypropylene and poly (4-methyl-1-pentene) or mixtures these polyolefins with each other or with other polyolefins.
  • the advantage is the use of poly (4-methyl-1-pentene) or of one Mixture of poly (4-methyl-1-pentene) with polypropylene. This allows high Realize gas transfer rates with good mechanical properties of the membranes.
  • compounds A and B which together form the solvent system, are use such compounds that meet the stated conditions.
  • polyethylene as a polymer component come as Compound A preferably soybean oil, palm kernel oil, isopropyl myristate or mixtures from here to use.
  • Castor oil then proves to be advantageous as compound B.
  • polypropylene as the polymer component preferably as compound A N, N-bis (2-hydroxyethyl) tallow fatty amine, dioctyl phthalate, Soybean oil, palm kernel oil or mixtures thereof are used.
  • connection B can advantageously be diethyl phthalate, glycerol triacetate, castor oil or mixtures use from here.
  • poly (4-methyl-1-pentene) as polyolefin come as compound A preferably palm kernel oil, dibutyl phthalate, Dioctyl phthalate, butyl stearate or mixtures thereof in question.
  • compound A preferably palm kernel oil, dibutyl phthalate, Dioctyl phthalate, butyl stearate or mixtures thereof in question.
  • glycerol triacetate, diethyl phthalate, castor oil, N, N-bis (2-hydroxyethyl) tallow fatty amine, Soybean oil, glycerol diacetate, glycerol monoacetate or mixtures proved to be advantageous from this. This has been particularly advantageous Use of glycerol triacetate as compound B.
  • the polymer fraction of the mixture from which the solution is formed is preferably is, at 30-60 wt .-% and the proportion of the solvent system consisting of the Compounds A and B, at 70-40% by weight.
  • the polymer content is particularly preferably at 35-50% by weight and the proportion of compounds A and B at 65-50 Wt .-%.
  • the polymer component, the compounds A and B or the polymer solution other substances such as Antioxidants, nucleating agents, Fillers, components to improve biocompatibility, i.e. blood compatibility when using the membrane in oxygenation, e.g. Vitamin E, and the like are added as additives.
  • the polymer solution formed from the polymer component and the solvent system is formed into a shaped body by means of suitable molding tools in order to finally, a membrane, preferably in the form of a flat membrane or hollow fiber membrane to obtain.
  • a membrane preferably in the form of a flat membrane or hollow fiber membrane to obtain.
  • Common molds such as slot dies, Watering boxes, squeegees, profiled nozzles, ring slot nozzles or hollow thread nozzles be used.
  • Hollow fiber membranes are preferred using the method according to the invention manufactured.
  • the polymer solution through the annular gap corresponding hollow thread nozzles to the shaped body, i.e. extruded into hollow thread.
  • a fluid is metered through the central bore of the hollow thread nozzle, which is used as an inner filling acts, which forms and stabilizes the lumen of the hollow fiber membrane.
  • the extruded hollow fiber or the resulting hollow fiber membrane then has a Lumen-facing surface, the inner surface, and a lumen-facing surface through the wall of the hollow thread or the hollow fiber membrane from the inner surface separate surface, the outer surface.
  • the shaped body is so formed by means of a solid or liquid Cooling medium cooled that a thermodynamic non-equilibrium liquid-liquid phase separation in the molded body, i.e. in the molded polymer solution takes place and further solidifies and solidifies the polymer structure.
  • the cooling medium tempered to a temperature below the solidification temperature.
  • the invention is to generate the desired integrally asymmetrical Membrane with separation layer to use as a cooling medium such a medium the polymer component even when the medium is heated to the mold temperature does not dissolve and does not react chemically with it.
  • the use of such Cooling medium is largely responsible for the formation of a separation layer with a denser structure.
  • Such a requirement for the cooling medium includes e.g.
  • the cooling medium can also be a solid one Be a fabric or a solid surface, e.g. in the form of a glass plate or a metal plate or in the form of an appropriately tempered or cooled chill roll, on which the molded body is placed.
  • the solid cooling medium a high thermal conductivity and particularly preferably consists of a metallic Material.
  • a cooling medium which is a liquid.
  • This is particularly preferred liquid used as cooling medium is a non-solvent for the polymer component, i.e. it dissolves the polymer component when heated to at most its boiling point not a homogeneous solution.
  • the liquid used as the cooling medium may also contain a component that is a solvent for the polymer component or it can also be a mixture of different non-solvents, as long as they total the polymer component at temperatures up to at least the mold temperature does not solve.
  • the strength of the non-release character of the cooling medium the tightness of the separating layer that forms affected.
  • Process is therefore used as a cooling medium, a liquid which strong non-solvent for the polymer component.
  • the cooling medium is preferably a homogeneous, single-phase liquid at the cooling temperature. hereby is the production of membranes with particularly homogeneous surface structures guaranteed.
  • Such a liquid cooling medium can be used, which with the Solvent system is miscible into a homogeneous solution or one which does not loosen the connections forming the solvent system.
  • the cooling medium preferably has one Temperature that is at least 100 ° C below the phase separation temperature is, and particularly preferably a temperature which is at least 150 ° C below the phase separation temperature is. It is particularly advantageous if the Temperature of the cooling medium is less than 50 ° C. In individual cases, cooling can at temperatures below room temperature may be required. It is also possible to carry out the cooling in several steps.
  • the liquid cooling medium is preferably located in a shaft or in a spinning tube through which the shaped body then passes for cooling.
  • the cooling medium and the shaped body are generally in the same direction through the shaft or the spinning tube.
  • Molded body and cooling medium can pass through the spinning tube at the same or different linear speed be performed, either the molded body or the Cooling medium which can have a higher linear velocity.
  • Such process variants are described, for example, in DE-A-28 33 493 or in EP-A-133 882.
  • the inner filling used in the extrusion of hollow threads can be gaseous or it can be a liquid.
  • a liquid must be selected that contains the polymer component in the molded polymer solution below the critical separation temperature the polymer solution essentially does not dissolve. Otherwise, the same liquids are used as they are used as cooling medium can be.
  • hollow fiber membranes can also be used produce a separating layer both on the outside and on the inside have or also hollow fiber membranes, the only on the inside Have separation layer.
  • the inner filling is then preferably one Non-solvent for the polymer component and particularly preferably around a strong one Non-solvent for the polymer component.
  • the inner filling can be done with the solvent system be miscible into a homogeneous single-phase solution.
  • the inner filling is gaseous, it can be air, a vaporous substance or preferably nitrogen or other inert gases.
  • the exit surface of the mold and the surface of the cooling medium are spatially spaced by a gap that from the molded body is run through before contact with the cooling medium. It can be about act an air gap, but the gap can also with another gaseous Atmosphere, and it can also be heated or cooled.
  • the polymer solution can also directly after cooling from the mold with the cooling medium be brought into contact.
  • the molds exiting the mold i.e. the emerging from the mold, molded polymer solution, at least with one of its before cooling Surfaces, preferably with the surface on which the separating layer is formed should be one, the evaporation of compound A and / or the compound B exposed to the gaseous atmosphere, i.e. an atmosphere in which allows the evaporation of compound A and / or compound B.
  • Prefers air is used to form the gaseous atmosphere.
  • nitrogen or other inert gases are preferably used, or gaseous ones Media.
  • the gaseous atmosphere is advantageously air-conditioned, and the gaseous atmosphere usually has a temperature that is below the mold temperature lies.
  • the molded body is at least one of its surfaces prefers the gaseous for at least 0.5 ms Exposed to atmosphere.
  • mold and cooling medium be spatially spaced so that a gap is formed between them, which contains the gaseous atmosphere and which the molded body passes through becomes.
  • flat membranes For example, in the manufacture of flat membranes, e.g. through a slot die extruded polymer solution as a flat film first passed through a gap through an air gap, for example, before it is cooled.
  • the flat film is on all sides, i.e. with their two surfaces as well as their Side edges surrounded by the gaseous atmosphere and it will result in the Flat membrane on both surfaces the formation of the interface affected.
  • the flat film is extruded directly onto a heated one Carrier e.g.
  • the one leaving the nozzle can Hollow thread can also be passed through a gap between the nozzle and the cooling medium is formed and which contains the gaseous atmosphere.
  • the structure of the separating layer can also be distorted by the formed one Polymer solution below the nozzle, i.e. especially influenced in the air gap be, the delay by setting a difference between the exit speed the polymer solution from the mold and the speed the first extraction device for the cooled molded body is generated.
  • the compounds A and B After the polymer structure has cooled and solidified, the compounds A and B usually removed from the molded body. The distance can be, for example done by extraction. Such extraction agents are preferred used, which do not solve the polymer or the polymers, but which are miscible with the connections A and B. Then drying at elevated Temperatures may be required to remove the extractant from the membrane.
  • Useful extractants are acetone, methanol, ethanol and preferred Isopropanol.
  • the two compounds A and B may also be appropriate to use the two compounds A and B to leave either both or one at least partially in the molded body and extract only one of the connections or none of the connections.
  • other components added to the compounds A and / or B as additives can remain in the membrane structure and thus e.g. as functional Serve active fluids.
  • functional fluids Microporous polymers containing are described in DE-A 27 37 745.
  • the membrane Before or after removing at least a substantial portion of the solvent system the membrane may be slightly stretched, in particular to to modify the properties of the separating layer in a targeted manner.
  • the membrane may be slightly stretched, in particular to to modify the properties of the separating layer in a targeted manner.
  • the membrane can be in a substantially dense separation layer by stretching Pores are generated and / or the pore size of the separating layer is based on the particular application required size of the resulting membrane.
  • the drawing step can therefore be carried out by means of the method according to the invention also manufacture membranes for nanofiltration or for ultrafiltration.
  • the method according to the invention can preferably be used for the production of hydrophobic integral asymmetric membranes especially for gas separation or use for gas exchange, the membranes mainly consisting of at least a polymer selected from the group of polyolefins are, have a first and a second surface and an intermediate Support layer, which has a sponge-like, open-pore microporous structure, and adjacent to this support layer on at least one of the surfaces Separating layer with a denser structure, the separating layer having at most pores has an average diameter ⁇ 100 nm, the support layer free of macrovoids is, the pores in the support layer are essentially isotropic on average and the membrane has a porosity in the range from greater than 30% by volume to less than 75% by volume. Therefore, the invention further relates to such a membrane, which means of the method according to the invention can be produced.
  • the have particularly preferably membranes produced by means of the method according to the invention have a density Separating layer.
  • the mean value is the average diameter of the pores in the separating layer understood from the diameters of the pores in the surface, which as Separating layer is formed, wherein a scanning electron micrograph at 60000 times magnification. With the image analysis evaluation a circular area is assumed for the pores.
  • the average pore diameter is the arithmetic mean of all on a membrane surface of approx. 8 ⁇ m x 6 ⁇ m with 60000x visible pores. In the invention manufactured membranes existing pores in the surface that the separation layer are uniform, i.e. homogeneous over this surface distributed.
  • the membranes Due to their structure, these membranes are characterized by high gas flows and high gas transfer rates with high security against breakthrough the liquid from which when using the membrane according to the invention a gas component is separated for gas transfer or the one gaseous component Component should be added, as well as good mechanical properties out.
  • the membrane has a high volume porosity, which essentially is determined by the structure of the support layer, and a defined one Separating layer with a small thickness.
  • the support layer of the membranes produced by the method according to the invention can, as already stated, have a different structure.
  • the support layer has a sponge-like cellular and open-pore Structure on where the pores are described as enclosed microcells can be that of channels, smaller pores or passages with each other are connected.
  • the support layer has a non-cell shape Structure in which the polymer phase and the pores penetrate Train network structures.
  • the support layer is free of Macrovoids, i.e. free of such pores, which in the literature are often called finger pores or caverns.
  • the pores of the support layer can have any geometry and e.g. of elongated, cylindrical, round shape or more or less irregular Be in shape.
  • membranes produced are essentially the pores in the support structure on average isotropic. This means that, although the individual pores can also have an elongated shape, averaged over all pores in all Spatial directions have essentially the same extent, with deviations between the expansions in the individual spatial directions of up to 20% are included.
  • the volume porosity is too low, i.e. too small a proportion of pores on the total volume of the membrane are the achievable gas flows and Gas transfer rates too low.
  • an excessive proportion of pores in the Membrane to poor mechanical properties, and the membrane can be no longer process without problems in subsequent processing processes.
  • through of the method according to the invention can preferably membranes with a Volume porosity in the range from greater than 30% by volume to less than 75% by volume, and particularly preferably in the range from greater than 50% by volume to less than 75% by volume produce.
  • the membranes thus produced can only have one on one of their surfaces Have separating layer, but they can also have one on their two surfaces Have separation layer.
  • the interface has an impact on the transfer rates or the gas flows, but also on the breakthrough time, i.e. on the Period of time that the membranes are against a breakthrough of the liquid who separated a gaseous component when using the membrane or the a gaseous component is to be added, or opposite one Breakthrough of components contained in the liquid are safe. So result very long breakthrough times with a dense separating layer, but they are The transfer rates are limited in size because the gas transfer occurs in dense membrane layers the difference is made only by a comparatively slow solution diffusion to the much larger Knudsen flow in porous structures. In the event of a nanoporous separation layer, however, the gas transfer rates are compared to one dense separation layer increases, but then shorter due to the pores Breakthrough times.
  • the thickness of the separating layer must not be too small, as this creates a risk for defects and thus e.g. for a breakthrough.
  • the time until an actual breakthrough is still relatively long because of these Membranes are not a preferred direction for the flow of a liquid, but rather the distance to be covered by the liquid due to the pore structure is winding.
  • the membranes that can be seen after the mentioned melt stretching processes are produced and in which due to pronounced anisotropy of the pores is a preferred direction for the flow of Liquids from one surface to another result.
  • the thickness of the separating layer is therefore preferably between 0.01 ⁇ m and 5 ⁇ m and particularly preferably between 0.1 ⁇ m and 2 ⁇ m.
  • Outstanding membranes according to the invention with a separating layer thickness are suitable between 0.1 ⁇ m and 0.6 ⁇ m.
  • the thickness of the separating layer can be according to the invention Process manufactured membranes in a simple manner Measure the layer using those created using scanning electron microscopy Fracture images or ultra-thin section characterizations created using transmission electron microscopy be determined.
  • the membranes preferably produced by means of the method according to the invention have a sufficiently high permeability of the membranes for use in blood oxygenation and thus achieve sufficiently high gas flows. Values of at least 1 ml / (cm 2 * min * bar) are achieved for the gas flow Q for CO 2 , Q (CO 2 ).
  • Membranes are the oxygenation of blood.
  • how plasma breakthrough time does matter i.e. the time the Membrane is stable to breakthrough blood plasma.
  • a plasma breakthrough is a much more complex process than the mere penetration of a hydrophilic liquid through a hydrophobic membrane.
  • a plasma breakthrough is caused by that hydrophilization occurs initially through proteins and phospholipids contained in the blood of the pore system of the membrane and in a downstream suddenly, blood plasma penetrates into the hydrophilized pore system takes place.
  • the plasma breakthrough time is therefore the critical parameter for a liquid breakthrough considered.
  • the membranes according to the invention preferably have a plasma breakthrough time of at least 20 hours, particularly preferred a plasma breakthrough time of at least 48 hours.
  • the transition generally takes place in the membranes produced according to the invention from the porous support layer to the separation layer in a narrow area of the membrane wall.
  • Processed membrane changes the membrane structure at the transition from the separation layer to the support layer abruptly, i.e. the membrane structure changes essentially seamless and erratic from the microporous support layer to the interface.
  • Membranes with such a structure point towards such Membranes with a slow, gradual transition from the interface to the support layer the advantage of a higher permeability of the support layer for transferring gases because the support layer in its adjacent to the separation layer Area is less compact.
  • these are by means of the method according to the invention
  • Membranes produced flat membranes, these preferably a Have thickness between 10 and 300 microns, particularly preferably between 30 and 150 microns.
  • These separating layers can only be implemented on their inner surface, i.e. on their surface facing the lumen, or only on their outer surface, i.e. have the surface facing away from the lumen or both on its inner surface and also have a separating layer on their outer surface.
  • the separating view is on the outer surface.
  • These hollow fiber membranes preferably have an outer diameter between 30 and 3000 ⁇ m, particularly preferably an outer diameter between 50 and 500 ⁇ m.
  • a wall thickness of the hollow fiber membrane between 5 and 150 ⁇ m is particularly advantageous favorable a thickness between 10 and 100 microns.
  • Hollow fiber membranes can be easily created using the method according to the invention with excellent mechanical properties, in particular with a breaking strength of at least 70 cN and an elongation at break of at least 75%, which means problem-free further processing in subsequent textile processing steps is possible.
  • This is how it is when using hollow fiber membranes as favorable in terms of the performance characteristics of membrane modules made therefrom proven when the hollow fiber membranes are first used, for example suitable knitting methods for mats of essentially parallel to each other Hollow fiber membranes are processed, from which then appropriate bundles getting produced.
  • the method according to the invention can therefore be used on the one hand membranes for gas separation tasks, in which, for example, a single gas component selectively from a mixture of at least two gases separated or a single gas component in a mixture of at least two gases is enriched, or use for gas transfer tasks where selectively removes a gas dissolved in a liquid from that liquid is dissolved, and / or a gas from a mixture of gases in a liquid becomes.
  • a single gas component selectively from a mixture of at least two gases separated or a single gas component in a mixture of at least two gases is enriched
  • gas transfer tasks where selectively removes a gas dissolved in a liquid from that liquid is dissolved, and / or a gas from a mixture of gases in a liquid becomes.
  • the pore size of the interface e.g.
  • membranes for the Nanofiltration such as preferred for the separation of low molecular weight substances from non-aqueous media or for ultrafiltration such as for the treatment of fresh water, waste water or process water or also for applications in Area of the food or dairy industry.
  • a drop of isopropanol, which is colored blue for better visibility of the effects is placed on the surface of a membrane sample.
  • the penetration behavior of the drop of isopropanol in the membrane surface is visually observed and provides qualitative information about the tightness of the membrane surface and thus about the presence of a separation layer with a denser structure. This penetrates an open-pore surface of the isopropanol drops immediately into the membrane surface and colors it blue. A dense surface does not allow spontaneous wetting with isopropanol.
  • a phospholipid solution tempered to 37 ° C 1.5 g L- ⁇ -phosphatidy-LCholine dissolved in 500 ml physiological saline solution
  • a pressure of 1.0 bar with a flow of 6 l / (min * 2m 2 ) guided along one surface of a membrane sample.
  • Air is allowed to flow along the other surface of the membrane sample and is passed through a cold trap after leaving the membrane sample.
  • the weight of the liquid collected in the cold trap is measured as a function of time. The time that elapses before the weight increases significantly, ie until the first significant fluid accumulation in the cold trap, is referred to as the plasma breakthrough time.
  • a sample of at least 0.5 g of the membrane to be examined is weighed out dry.
  • the membrane sample is then placed in a membrane but not swelling liquid soaked for 24 hours, so the Liquid penetrates all pores. This can be seen visually from the fact that the Membrane sample changes from an opaque to a glassy, transparent state.
  • the membrane sample is then removed from the liquid at which Membrane sample adhering liquid removed by centrifugation at approx. 1800 g and the mass of wet so pretreated, i.e. liquid-filled membrane sample certainly.
  • a membrane sample is used on one of its sides to determine the gas flows the gas to be measured is subjected to a constant test pressure of 2 bar.
  • the gas is introduced into the lumen of the hollow fiber membrane. It becomes the volume flow passing through the wall of the membrane sample of the gas is determined and with regard to the test pressure and the gas flow Area of the membrane sample standardized.
  • the inner surface of the membrane surrounding the lumen is inserted.
  • the polymer solution from Example 1 was used to produce a hollow fiber membrane used.
  • the homogeneous solution was passed through a hollow fiber nozzle with a Outside diameter of the annular gap of 1.2 mm and an annular gap of 350 ⁇ m extruded and after an air gap of 10 cm by glycerol triacetate as cooling medium guided.
  • the cooling medium was kept at room temperature.
  • a hollow fiber membrane was obtained, which is in the scanning electronic recording on the outside a dense separating layer (Fig. 3) and in the inside of the wall had a spongy, open-pore, microporous support structure (FIG. 4).
  • the tight outside of the membrane showed no spontaneous wettability with isopropanol.
  • Example 2 The procedure was as in Example 1, with a solution of 25% by weight poly (4-methyl-1-pentene) in 75% by weight of a mixture of 93% by weight of dioctyl phthalate and 7 wt .-% glycerol monoacetate was used as the solvent system.
  • the on Homogeneous solution tempered at 255 ° C. was kept at a room temperature Glass plate squeegee with the help of a squeegee, the distance to the glass plate 250 ⁇ m scam. After cooling and the associated phase separation, a porous one Obtained polymer film, which is subsequently extracted with isopropanol and then dried at room temperature.
  • Poly- (4-methyl-1-pentene) was gradually increased at 265 ° C in an extruder 300 ° C rising temperatures melted and by means of a gear pump continuously fed to a dynamic mixer.
  • the solvent system consisting of 70% by weight dioctyl phthalate and 30% by weight glycerol triacetate, was also fed to the mixer in which the polymer together with the solvent system at a temperature of 290 ° C to a homogeneous solution with a polymer concentration of 35 wt .-% and Concentration of the solvent system of 65 wt .-% was processed.
  • This solution was a hollow thread nozzle with an outer diameter of 1.2 mm and a Annular gap of 350 microns supplied and above the phase separation temperature 245 ° C extruded into a hollow thread. Nitrogen was used as the inner filling. After an air gap of 25 mm, the hollow thread passed through an approximately 1 m long spinning tube, which is flowed through by glycerol triacetate at 18 ° C as the cooling medium has been. The hollow thread, which had solidified as a result of cooling in the spinning tube, became withdrawn from the spinning tube at a take-off speed of 72 m / min a coil wound, then extracted first with isopropanol and then dried at approx. 120 ° C.
  • a hollow fiber membrane was obtained with an outside diameter of 412 ⁇ m and a wall thickness of 93 ⁇ m, for which no pores were detectable on its outer surface even with a magnification of 60,000 by scanning electronic (SEM) examination (FIG. 7).
  • SEM scanning electronic
  • FIG. 7 In the fracture pattern of a fracture surface perpendicular to the longitudinal axis of the hollow fiber membrane, the sponge-like, open-pore microporous support layer can be seen, which is covered by the approx. 0.2 ⁇ m thick separating layer (FIG. 8).
  • a volume porosity of 57% and a CO 2 flow of 2.82 ml / (cm 2 * min * bar) were determined for the membrane according to this example.
  • the membrane had a plasma breakthrough time of more than 72 hours. After this time the test was canceled.
  • Polypropylene (Vestolen® P9000) was gradually extruded from Melted 210 ° C to 240 ° C rising temperatures and by means of a Gear pump continuously fed to a dynamic mixer.
  • the solvent system consisting of 75 wt .-% soybean oil and 25 wt .-% castor oil, was a metering pump also fed to the mixer in which the polymer together with the solvent system for 6 min at a temperature of 240 ° C to a homogeneous solution with a polymer concentration of 38 wt .-% and a concentration of the solvent system of 62% by weight was processed.
  • This solution was a hollow thread nozzle with an outer diameter of 1.2 mm and a Annular gap of 350 microns fed and above the phase separation temperature at 232 ° C. extruded into a hollow thread. Nitrogen was used as the inner filling.
  • the hollow thread passed through an approximately 1 m long spinning tube, which is flowed through by glycerol triacetate at 18 ° C as the cooling medium has been.
  • the hollow fiber solidified as a result of the cooling in the spinning tube was with a Take-off speed of 72 m / min drawn from the spinning tube onto a spool wound up, then first extracted with isopropanol and then at approx. Dried at 120 ° C.
  • the hollow fiber membrane obtained had a sponge-like, open-pore microporous support structure in the fracture pattern of a fracture surface perpendicular to the longitudinal axis of the hollow fiber membrane, which was covered to the outside of the membrane by a separating layer with a thickness of about 0.3 ⁇ m (FIG. 9).
  • a separating layer with a thickness of about 0.3 ⁇ m (FIG. 9).
  • individual pores with a size of up to approx. 0.1 ⁇ m were found on the outer membrane surface.
  • For the membrane according to this example had an outside diameter of 393 ⁇ m and a wall thickness of 80 ⁇ m. It had a volume porosity of greater than 55% by volume and a CO 2 flow of 74.5 ml / (cm 2 * min * bar).
  • Example 4 The procedure was as in Example 4, with a mixture as the solvent system from 97% by weight of dibutyl phthalate and 3% by weight of glycerol triacetate was used. The The nozzle was heated to 240 ° C and the air gap was 20 mm.
  • a hollow fiber membrane was obtained with an outside diameter of 413 ⁇ m and a wall thickness of 88 ⁇ m. In the SEM examination, no pores were found even with a magnification of 60,000 on the outer surface. In the fracture pattern of a fracture surface perpendicular to the longitudinal axis of the hollow fiber membrane, a spongy, open-pore microporous support structure was visible, which was covered by the approx. 0.3 ⁇ m thick separating layer. A volume porosity of 57% and a CO 2 flow of 4.90 ml / (cm 2 * min * bar) were determined for the membrane according to this example. The membrane had a plasma breakthrough time of more than 72 hours. After this time the test was canceled.
  • the solution of poly (4-methyl-1-pentene) in dioctyl phthalate / glycerol monoacetate used in Example 3 was used as a solvent system through a hollow thread nozzle an outer diameter of the annular gap of 1.2 mm and an annular gap of 350 ⁇ m extruded and after an air gap of 10 cm by dioctyl phthalate as a cooling medium guided.
  • the cooling medium was kept at room temperature.
  • dioctylphthalate itself is a solvent for poly (4-methyl-1-pentene).
  • the hollow fiber membrane obtained had a variety of on its outer surface fine pores.
  • the fracture pattern of a fracture surface perpendicular to the longitudinal axis of the A separating layer was not recognizable in the hollow fiber membrane; extend porous areas down to the surface (Fig. 10).
  • the outer surface was spontaneous with isopropanol wettable.
  • a hollow fiber membrane made of polypropylene was produced as in Example 5. in the In contrast to Example 5, however, soybean oil was used as the cooling medium, which was tempered to 45 ° C. Soybean oil is a weak one in terms of polypropylene Solver.
  • a hollow fiber membrane with an outer diameter of 414 ⁇ m and a wall thickness of 90 ⁇ m was obtained, the outer surface of which, according to the SEM photographs, had a pronounced open-pore structure (FIG. 11).
  • the membrane according to this example had a CO 2 flow of 204 ml / (cm 2 * min * bar) and a plasma breakthrough time of only 4 hours. Such a membrane is probably suitable for standard applications for blood oxygenation, but not for long-term oxygenation.
  • 25 wt% poly (4-methyl-1-pentene) was mixed at 75 ° C in 75 wt% of a mixture from 90% by weight isopropyl myristate and 10% by weight glycerol monoacetate, i.e. corresponding the definition of the present invention of a mixture of a strong Solver and a strong non-solvent, solved.
  • the homogeneous tempered to 255 ° C and clear solution was kept at room temperature with a doctor blade Glass plate squeegee, with a distance of 250 between squeegee and glass plate ⁇ m was set.
  • the cooled porous polymer film was extracted with isopropanol and then dried at room temperature.
  • the flat membrane obtained had a pronounced compact and over its thickness z.T. particulate structure with intervening pore channels (Fig. 13), the down to the surface that faced the glass side during manufacture was extended and there were pores with Formed sizes above 0.1 microns (Fig. 14). A separation layer was not recognizable.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Claims (23)

  1. Procédé de fabrication d'une membrane hydrophobe asymétrique à peau intégrée, comportant une structure de support microporeuse à pores ouverts, de type éponge, et une couche séparatrice de structure plus dense que la structure de support, lequel procédé comporte au moins les étapes suivantes :
    a) le fait de préparer une solution homogène de 20 à 90 % en poids d'un composant polymère, constitué d'au moins un polymère choisi dans l'ensemble des polyoléfines, dans 80 à 10 % en poids d'un système solvant contenant un composé A et un composé B qui, à la température de dissolution, sont liquides et miscibles l'un à l'autre, le mélange constitué par le composant polymère, le composé A et le composé B présentant une température critique de démixtion et une température de solidification, ainsi qu'une lacune de miscibilité à l'état liquide au-dessous de la température critique de démixtion, un solvant du composant polymère étant choisi pour composé A, et le composé B faisant monter la température de démixtion d'une solution constituée du composant polymère et du composé A ;
    b) le fait de mettre en forme la solution pour en faire un corps formé doté d'une première surface et d'une deuxième surface, dans un outil de formage qui se trouve à une température supérieure à la température critique de démixtion ;
    c) le fait de faire refroidir le corps formé, à l'aide d'un milieu réfrigérant maintenu à une température de refroidissement inférieure à la température de solidification, à une vitesse telle qu'il se produit une séparation de phases liquide/liquide, hors équilibre thermodynamique, en une phase riche en polymère et une phase pauvre en polymère, et qu'ensuite la phase riche en polymère se solidifie en restant à une température inférieure à la température de solidification ;
    d) et le cas échéant, le fait d'éliminer du corps formé le composé A et le composé B ;
    et lequel procédé est caractérisé en ce que l'on choisit pour composé A un solvant médiocre du composant polymère pour lequel la température de démixtion d'une solution à 25 % en poids du composant polymère dans ce solvant est inférieure de moins de 10 °C au point de fusion du composant polymère pur, en ce que l'on choisit pour composé B un non-solvant du composant polymère qui, chauffé jusqu'à son point d'ébullition, ne dissout pas le composant polymère en une solution homogène, et en ce que, pour faire refroidir le corps formé, on le met en contact avec un milieu réfrigérant solide ou liquide qui, aux températures allant jusqu'à la température de l'outil de formage, ne dissout pas le composant polymère et ne réagit pas chimiquement avec lui.
  2. Procédé conforme à la revendication 1, caractérisé en ce que le composé B est un médiocre non-solvant du composant polymère.
  3. Procédé conforme à l'une ou plusieurs des revendications 1 et 2, caractérisé en ce que le milieu réfrigérant est un liquide qui est un non-solvant du composant polymère.
  4. Procédé conforme à la revendication 3, caractérisé en ce que le milieu réfrigérant contient du composé B.
  5. Procédé conforme à la revendication 3, caractérisé en ce que le milieu réfrigérant est un liquide qui est un bon non-solvant du composant polymère.
  6. Procédé conforme à l'une ou plusieurs des revendications 1 à 5, caractérisé en ce que l'on utilise un milieu réfrigérant qui, à la température de refroidissement, est un liquide homogène monophasique.
  7. Procédé conforme à l'une ou plusieurs des revendications 1 à 6, caractérisé en ce que le milieu réfrigérant se trouve à une température inférieure d'au moins 100 °C à la température critique de démixtion.
  8. Procédé conforme à l'une ou plusieurs des revendications 1 à 7, caractérisé en ce que l'on expose le corps formé, après l'avoir retiré de l'outil de formage et avant de le faire refroidir, par au moins l'une de ses surfaces, à un environnement favorisant l'évaporation du composé A et/ou du composé B.
  9. Procédé conforme à l'une ou plusieurs des revendications 1 à 8, caractérisé en ce qu'il y a 30 à 60 % en poids de composant polymère dissous dans 70 à 40 % en poids de système solvant.
  10. Procédé conforme à l'une ou plusieurs des revendications 1 à 9, caractérisé en ce que ledit polymère contenu, au nombre d'au moins un, dans le composant polymère est au moins une polyoléfine exclusivement constituée de carbone et d'hydrogène.
  11. Procédé conforme à la revendication 10, caractérisé en ce que ladite polyoléfine au nombre d'au moins une est un poly(4-méthyl-1-pentène).
  12. Procédé conforme à la revendication 10, caractérisé en ce que ladite polyoléfine au nombre d'au moins une est un polypropylène.
  13. Procédé conforme à la revendication 10, caractérisé en ce que ladite polyoléfine au nombre d'au moins une est un mélange constitué d'un poly(4-méthyl-1-pentène) et d'un polypropylène.
  14. Procédé conforme à la revendication 10, caractérisé en ce que ladite polyoléfine au nombre d'au moins une est un polyéthylène.
  15. Procédé conforme à la revendication 11, caractérisé en ce que l'on emploie comme composé A de l'huile de palmiste, du phtalate de dibutyle, du phtalate de dioctyle ou du stéarate de butyle, ou un mélange de ces composés.
  16. Procédé conforme à la revendication 11, caractérisé en ce que l'on emploie comme composé B du triacétate de glycérol, du phtalate de diéthyle, de l'huile de ricin, de la N,N-bis(2-hydroxyéthyl)suifamine, de l'huile de soja, du diacétate de glycérol ou du monoacétate de glycérol, ou un mélange de ces composés.
  17. Procédé conforme à la revendication 12, caractérisé en ce que l'on emploie comme composé A de la N,N-bis(2-hydroxyéthyl)suifamine, du phtalate de dioctyle, de l'huile de soja ou de l'huile de palmiste, ou un mélange de ces composés.
  18. Procédé conforme à la revendication 12, caractérisé en ce que l'on emploie comme composé B du phtalate de dibutyle, du phtalate de diéthyle, du triacétate de glycérol ou de l'huile de ricin, ou un mélange de ces composés.
  19. Procédé conforme à la revendication 14, caractérisé en ce que l'on emploie comme composé A de l'huile de soja, de l'huile de palmiste ou du myristate d'isopropyle, ou un mélange de ces composés.
  20. Procédé conforme à la revendication 14, caractérisé en ce que l'on emploie comme composé B de l'huile de ricin.
  21. Procédé conforme à l'une ou plusieurs des revendications 1 à 20, caractérisé en ce que la proportion pondérale de composé B dans le système solvant vaut de 1 à 45 %.
  22. Procédé, conforme à l'une ou plusieurs des revendications 1 à 21, de fabrication de membranes en fibres creuses.
  23. Utilisation, pour oxygéner du sang, de membranes fabriquées selon un procédé conforme à l'une ou plusieurs des revendications 1 à 22.
EP00909086A 1999-01-22 2000-01-19 Procede de fabrication d'une membrane polyolefinique integralement asymetrique Expired - Lifetime EP1140331B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19902566 1999-01-22
DE19902566 1999-01-22
PCT/EP2000/000391 WO2000043113A1 (fr) 1999-01-22 2000-01-19 Procede de fabrication d'une membrane polyolefinique integralement asymetrique

Publications (2)

Publication Number Publication Date
EP1140331A1 EP1140331A1 (fr) 2001-10-10
EP1140331B1 true EP1140331B1 (fr) 2003-01-02

Family

ID=7895141

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00909086A Expired - Lifetime EP1140331B1 (fr) 1999-01-22 2000-01-19 Procede de fabrication d'une membrane polyolefinique integralement asymetrique

Country Status (9)

Country Link
US (1) US6375876B1 (fr)
EP (1) EP1140331B1 (fr)
JP (1) JP4095773B2 (fr)
KR (1) KR100654592B1 (fr)
CN (1) CN1136035C (fr)
AU (1) AU747646B2 (fr)
DE (1) DE50000994D1 (fr)
DK (1) DK1140331T3 (fr)
WO (1) WO2000043113A1 (fr)

Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR0007614B1 (pt) * 1999-01-21 2010-10-19 processo de preparação de membrana hidrofóbica integralmente assimétrica, e, membrana hidrofóbica.
US7229665B2 (en) 2001-05-22 2007-06-12 Millipore Corporation Process of forming multilayered structures
JP5062798B2 (ja) * 2001-10-04 2012-10-31 東レ株式会社 中空糸膜の製造方法
WO2003061812A2 (fr) * 2002-01-24 2003-07-31 Membrana Gmbh Membrane polyolefine presentant une structure integralement asymetrique et son procede de production
US6811696B2 (en) * 2002-04-12 2004-11-02 Pall Corporation Hydrophobic membrane materials for filter venting applications
US7071248B2 (en) * 2003-01-21 2006-07-04 Ashland Licensing And Intellectual Property, Llc Adhesive additives and adhesive compositions containing an adhesive additive
JP4427291B2 (ja) * 2003-09-03 2010-03-03 東亞合成株式会社 機能性膜の連続製造方法
JP5135221B2 (ja) 2005-09-09 2013-02-06 メムブラーナ ゲゼルシャフト ミット ベシュレンクテル ハフツング 血液から白血球を除去するための方法
US20070085235A1 (en) * 2005-10-18 2007-04-19 Boyle Timothy J Method and apparatus for continuously preparing crosslinked, solution-cast polymer film
US20070085234A1 (en) * 2005-10-19 2007-04-19 Boyle Timothy J Method and apparatus for solution casting film with secondary component
US20080088180A1 (en) * 2006-10-13 2008-04-17 Cash Audwin W Method of load shedding to reduce the total power consumption of a load control system
KR101199826B1 (ko) * 2006-12-14 2012-11-09 에스케이이노베이션 주식회사 효율적인 압출에 따른 폴리올레핀 미세다공막 제조방법
JP2008200589A (ja) * 2007-02-19 2008-09-04 Kansai Electric Power Co Inc:The ガス分離方法及びガス分離装置
CN102284232A (zh) * 2011-06-07 2011-12-21 北京萃亨科技有限公司 四氟乙烯生产尾气回收方法及其膜组件
CN103055724B (zh) * 2011-10-19 2015-05-13 华东理工大学 一种逆向热致相分离法制备聚砜类聚合物微孔膜的方法
US9005496B2 (en) * 2012-02-01 2015-04-14 Pall Corporation Asymmetric membranes
US10076620B2 (en) 2012-12-22 2018-09-18 Dmf Medical Incorporated Anesthetic circuit having a hollow fiber membrane
CN103464003B (zh) * 2013-09-24 2016-08-10 清华大学 一种制备聚丙烯中空纤维多孔膜的方法
TWI669152B (zh) * 2014-11-03 2019-08-21 美商3M新設資產公司 微孔性聚偏二氟乙烯平面膜及其製造方法
EP3235558A1 (fr) 2016-04-21 2017-10-25 3M Innovative Properties Company of 3M Center Membrane à fibres creuses destinée à être utilisée dans un circuit anesthésique
WO2019111157A1 (fr) * 2017-12-04 2019-06-13 King Abdullah University Of Science And Technology Procédés de fabrication de membranes poreuses
WO2020136568A1 (fr) * 2018-12-27 2020-07-02 3M Innovative Properties Company Membranes à fibres creuses avec agent de nucléation, leurs procédés de fabrication et d'utilisation
JP2022515479A (ja) * 2018-12-27 2022-02-18 スリーエム イノベイティブ プロパティズ カンパニー 非対称中空糸膜及びその製造並びに使用方法
CN111346520A (zh) * 2019-09-09 2020-06-30 杭州科百特过滤器材有限公司 一种非对称聚烯烃脱气膜及其制备方法
CN110538582A (zh) * 2019-09-09 2019-12-06 杭州科百特过滤器材有限公司 一种非对称聚烯烃膜的制备方法
JP7383266B2 (ja) * 2021-01-29 2023-11-20 プライムプラネットエナジー&ソリューションズ株式会社 オレフィン系樹脂多孔質体の製造方法
CN115028867B (zh) * 2022-07-01 2023-07-11 浙江大学 非对称丙烯/1-烯烃共聚物氧合膜及其制备方法和应用

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4247498A (en) * 1976-08-30 1981-01-27 Akzona Incorporated Methods for making microporous products
DK171108B1 (da) * 1976-08-30 1996-06-10 Akzo Nv Mikroporøst polymerlegeme samt dettes fremstilling og anvendelse
GB2008191B (en) * 1977-11-18 1982-05-12 Nippon Soken Uniflow two cycle internal combustion engines and methods of operating such engines
DE2833493C2 (de) 1978-07-31 1989-10-12 Akzo Gmbh, 5600 Wuppertal Hohlfäden
DE3205289C2 (de) * 1982-02-15 1984-10-31 Akzo Gmbh, 5600 Wuppertal Verfahren zur Herstellung von porösen Körpern mit einstellbarem Gesamtporenvolumen, einstellbarer Porengröße und einstellbarer Porenwandung
EP0133882B1 (fr) * 1983-07-30 1990-04-04 Akzo Patente GmbH Corps poreux
DE3803693A1 (de) 1987-03-10 1988-09-22 Akzo Gmbh Mehrlagiger hohlfadenwickelkoerper
EP0299381B2 (fr) 1987-07-11 1999-06-30 Dainippon Ink And Chemicals, Inc. Poumon artificiel du type à membrane et son procédé d'utilisation
US4980101A (en) * 1989-07-14 1990-12-25 The Dow Chemical Company Anisotropic microporous syndiotactic polystyrene membranes and a process for preparing the same
US5155144A (en) * 1990-10-29 1992-10-13 Manganaro James L Polysaccharide-based porous sheets
US5962544A (en) * 1995-12-07 1999-10-05 3M Microporous materials of ethylene-vinyl alcohol copolymer and methods for making same
WO1999004891A1 (fr) * 1997-07-23 1999-02-04 Akzo Nobel Nv Membrane en polyolefine integralement asymetrique pour echange gazeux

Also Published As

Publication number Publication date
KR20010103749A (ko) 2001-11-23
CN1336849A (zh) 2002-02-20
DE50000994D1 (de) 2003-02-06
AU747646B2 (en) 2002-05-16
CN1136035C (zh) 2004-01-28
WO2000043113A1 (fr) 2000-07-27
JP2002535114A (ja) 2002-10-22
AU3149800A (en) 2000-08-07
KR100654592B1 (ko) 2006-12-07
EP1140331A1 (fr) 2001-10-10
DK1140331T3 (da) 2003-04-07
JP4095773B2 (ja) 2008-06-04
US6375876B1 (en) 2002-04-23

Similar Documents

Publication Publication Date Title
EP1144096B1 (fr) Membrane polyolefinique integralement asymetrique
EP1140331B1 (fr) Procede de fabrication d'une membrane polyolefinique integralement asymetrique
EP0999889B1 (fr) Membrane en polyolefine integralement asymetrique pour echange gazeux
EP1469935B1 (fr) Procede de production de membranes polyolefine presentant une structure integralement asymetrique
EP2196254B1 (fr) Membrane PVDF hydrophobe résistant à l'ozone et ayant une stabilité mécanique élevée
EP0133882B1 (fr) Corps poreux
EP1893324B1 (fr) Membrane de microfiltration a comportement de filtration ameliore
EP2696963B1 (fr) Membrane de filtration macroporeuse
EP0357021B1 (fr) Procédé de fabrication de membranes
DE69233584T2 (de) Ultraporöse und mikroporöse Membranen
EP3003538B1 (fr) Membrane de polyfluorure de vinylidène microporeuse
EP0361085B1 (fr) Membrane intégrale asymétrique en polyéthersulfone, son procédé de fabrication et son application à l'ultrafiltration et la microfiltration
DE19518624C1 (de) Synthetische Trennmembran
DE60029239T2 (de) Hitzebeständiger mikroporöser film
EP3618943A1 (fr) Membrane plate hydrophobe à base de fluorure de polyvinylidène et procédé de fabrication de ladite membrane
DE2833493C2 (de) Hohlfäden
DE4421871A1 (de) Mehrschichtige Mikrofiltrationsmembran mit integrierter Vorfilterschicht und Verfahren zu ihrer Herstellung
CH644789A5 (de) Membran mit poroeser oberflaeche.
DE3016542A1 (de) Aethylen/vinylalkohol-copolymerhohlfasermembran und verfahren zu ihrer herstellung
EP1289636B1 (fr) Membrane polyamide a stabilite renforcee a l'hydrolyse et son procede de production
DE60111791T2 (de) Hohlfaser-Membrane und ihre Herstellung
DE10034098C2 (de) Hydrophobe mikroporöse Hohlfasermembran und Verfahren zur Herstellung dieser Membran sowie deren Verwendung in der Membranoxygenierung
DE3327638C2 (de) Verfahren und Vorrichtung zur Herstellung Poren aufweisender Formkörper
AT375024B (de) Filterelement
AT380179B (de) Verfahren zur herstellung einer membran mit poroeser struktur in form eines hohlfadens

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20010707

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE DK FR GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: 20030102:NOT ENGLISH

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: GERMAN

REF Corresponds to:

Ref document number: 50000994

Country of ref document: DE

Date of ref document: 20030206

Kind code of ref document: P

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20030429

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

Ref document number: 1140331E

Country of ref document: IE

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20031003

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20050112

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 20050121

Year of fee payment: 6

Ref country code: DK

Payment date: 20050121

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060119

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060131

Ref country code: DK

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060131

REG Reference to a national code

Ref country code: DK

Ref legal event code: EBP

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20060119

BERE Be: lapsed

Owner name: *MEMBRANA G.M.B.H.

Effective date: 20060131

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 17

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 50000994

Country of ref document: DE

Representative=s name: SCHROEDER OBERLEIN PATENTANWALTS UG (HAFTUNGSB, DE

Ref country code: DE

Ref legal event code: R081

Ref document number: 50000994

Country of ref document: DE

Owner name: 3M INNOVATIVE PROPERTIES COMPANY, SAINT PAUL, US

Free format text: FORMER OWNER: MEMBRANA GMBH, 42289 WUPPERTAL, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 50000994

Country of ref document: DE

Representative=s name: HETTSTEDT, STEPHAN, DR., DE

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

Owner name: 3M INNOVATIVE PROPERTIES COMPANY, US

Effective date: 20160323

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 50000994

Country of ref document: DE

Representative=s name: HETTSTEDT, STEPHAN, DR., DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 50000994

Country of ref document: DE

Representative=s name: HETTSTEDT, STEPHAN, DR., DE

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20181213

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20190121

Year of fee payment: 20

Ref country code: DE

Payment date: 20190108

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 50000994

Country of ref document: DE